This invention relates to improvements in a processing device which comprises: a lid, a plunger or other elongated member mounted in the lid in a manner such that, when the device is in use, the plunger can either be fixed in the lid, or the plunger can be rotated in either direction within the lid, while the lid remains stationary.
A developing device in which a plunger can be rotated in either direction by means of a radially extending arm serving as a handle and having a rotatable grip at its free end, while a cover member or lid remains stationary, has been described in U.S. Pat. No. 4,001,857 to Masai Ikechi et al, assigned to Fuji Photo Film Co., Ltd. However, the handle and the grip thereon protrude at all times from the upper end of the device and must be removed therefrom if unintentional rotation is to be avoided.